Presentation of unbalance information for electrical asset management

ABSTRACT

Disclosed herein is an approach that presents unbalance information obtained from electrical assets in a manner that facilitates management of the electrical assets. In one aspect, a screen view is generated that provides a visual representation of the electrical assets as partitioned into one or more groupings that are each based on a common operational characteristic associated with the electrical assets. The screen view also contains unbalance information that is associated with each of the electrical assets in the one or more groupings and at least one statistical measure that is associated with each of the one or more groupings.

BACKGROUND OF THE INVENTION

The present invention relates generally to electrical assets used withinan industrial process and more particularly to presenting unbalanceinformation obtained from the electrical assets onto a user interface ina manner that facilitates improved management of the electrical assets.

An industrial motor is one type of electrical asset that is used withinan industrial process. Three-phase motors such as induction motors andsynchronous motors are examples of typical motors that are widely usedin industrial processes such as a power generation plant. Althoughgenerally reliable in operation, a motor failure can adversely affectthe productivity of an industrial process. Consequently, motorprotection devices such as motor relays and meters have been used toprotect industrial motors from failing. In particular, these motorprotection devices provide protection against unbalanced loads,excessively high overcurrent faults, undervoltage conditions,overvoltage conditions, mechanical jams and load losses. As technologyfor motor protection devices has improved, so has the amount ofinformation that these devices are able to obtain. This information notonly includes data pertaining to the motors, but also data that relatesto the conditions of other loads that share the electrical buses of themotors. Despite the availability of all of the information from thesemodern motor protection devices, there is no easy way to decipher thisinformation in a manner that can facilitate monitoring and management ofthese motors while operating within their processes.

BRIEF DESCRIPTION OF THE INVENTION

In one aspect of the present invention, a computer system for presentingunbalance information from a plurality of electrical assets operating ina process is provided. The computer system comprises at least oneprocessing unit; memory operably associated with the at least oneprocessing unit; and an electrical asset management application storablein memory and executable by the at least one processing unit thatpresents the unbalance information generated from the plurality ofelectrical assets for management thereof. The electrical assetmanagement application is configured to: generate a visualrepresentation of the plurality of electrical assets operating in theprocess; partition the plurality of electrical assets in the visualrepresentation into one or more groupings that are each based on acommon operational characteristic associated with the plurality ofelectrical assets; obtain the unbalance information and associate theunbalance information with each of the plurality of electrical assets inthe one or more groupings; determine at least one statistical measurefor each of the one or more groupings that is based on the unbalanceinformation associated with each of the plurality of electrical assetsin the one or more groupings, wherein the at least one statisticalmeasure provides an indication of the presence of abnormal operationassociated with each of the one or more groupings; and display thevisual representation of the plurality of electrical assets aspartitioned within the one or more groupings, the display furthercomprising the unbalance information associated with each of theplurality of electrical assets in the one or more groupings and the atleast one statistical measure associated with each of the one or moregroupings.

In another aspect of the present invention, a method, performed on acomputer system, for monitoring a plurality of electrical assetsoperating in a process is provided. In this aspect of the presentinvention, the method comprises: using the computer system to performthe following: displaying a screen view that provides a visualrepresentation of the plurality of electrical assets operating in theprocess; displaying a screen view that facilitates partitioning theplurality of electrical assets in the visual representation into one ormore groupings that are each based on a common operationalcharacteristic associated with the plurality of electrical assets;obtaining unbalance information generated from the plurality ofelectrical assets as each operates in the process; associating theobtained unbalance information with each of the plurality of electricalassets in the one or more groupings; determining at least onestatistical measure for each of the one or more groupings that is basedon the unbalance information associated with each of the plurality ofelectrical assets in the one or more groupings, wherein the at least onestatistical measure provides an indication of the presence of abnormaloperation associated with each of the one or more groupings; anddisplaying a screen view that provides the visual representation of theplurality of electrical assets as partitioned within the one or moregroupings, the unbalance information associated with each of theplurality of electrical assets in the one or more groupings and the atleast one statistical measure associated with each of the one or moregroupings.

In a third aspect of the present invention, a computer-readable storagemedium storing computer instructions, which when executed, enables acomputer system to present unbalance information generated from aplurality of electrical assets operating in a process is disclosed. Inthis aspect of the present invention, the computer instructionscomprises: generating a visual representation of the plurality ofelectrical assets operating in the process; partitioning the pluralityof electrical assets in the visual representation into one or moregroupings that are each based on a common operational characteristicassociated with the plurality of electrical assets; obtaining theunbalance information from the plurality of electrical assets as eachoperates in the process; associating the obtained unbalance informationwith each of the plurality of electrical assets in the one or moregroupings; determining at least one statistical measure for each of theone or more groupings that is based on the unbalance informationassociated with each of the plurality of electrical assets in the one ormore groupings, wherein the at least one statistical measure provides anindication of the presence of abnormal operation associated with each ofthe one or more groupings; and generating a screen view that providesthe visual representation of the plurality of electrical assets aspartitioned within the one or more groupings, the unbalance informationassociated with each of the plurality of electrical assets in the one ormore groupings and the at least one statistical measure associated witheach of the one or more groupings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic block diagram of a system for managing a motor inan industrial process;

FIG. 2 shows a flow chart illustrating the operation of generatingscreen views like the ones depicted in FIGS. 3-7 that are used tofacilitate management of motors used in an industrial process accordingto one embodiment of the present invention;

FIG. 3 shows an example of a screen view that may be presented to a userof a computer system like the one shown in FIG. 1 that facilitatesmanagement of motors used in an industrial process according to oneembodiment of the present invention;

FIG. 4 shows an example of another screen view that may be presented toa user of a computer system like the one shown in FIG. 1 thatfacilitates management of motors used in an industrial process accordingto one embodiment of the present invention;

FIG. 5 shows an example of yet another screen view that may be presentedto a user of a computer system like the one shown in FIG. 1 thatfacilitates management of motors used in an industrial process accordingto one embodiment of the present invention;

FIG. 6 show an example of still another screen view that may bepresented to a user of a computer system like the one shown in FIG. 1that facilitates management of motors used in an industrial processaccording to one embodiment of the present invention; and

FIG. 7 show an example of yet another screen view that may be presentedto a user of a computer system like the one shown in FIG. 1 thatfacilitates management of motors used in an industrial process accordingto one embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Various embodiments of the present invention are directed to obtainingunbalance information generated from electrical assets that operate in aprocess and presenting this information in a manner that facilitatesmanagement of the assets and the process. In one embodiment, thepresentation of the unbalance information that facilitates management ofthe assets and the process includes generating a visual representationof the electrical assets operating in the process. Next, the electricalassets in the visual representation are partitioned into one or moregroupings that are each based on a common operational characteristic.The unbalance information generated from the electrical assets is thenobtained and associated with each of the assets in the one or moregroupings. At least one statistical measure is determined for each ofthe one or more groupings that is based on the unbalance informationassociated with each of the electrical assets in the one or moregroupings. Then at least one statistical measure provides an indicationof the presence of abnormal operation associated with each of the one ormore groupings. The visual representation of the electrical assets aspartitioned within the one or more groupings is displayed to anoperator, along with the unbalance information that is associated witheach of the assets in the one or more groupings and the at least onestatistical measure that is associated with each of the one or moregroupings. Technical effects of the various embodiments of the presentinvention include improving monitoring and management of theseelectrical assets while operating in the process. Improved monitoringand management of these electrical assets results in increasedproductivity of the process, as well as reduced warranty claims on theperformance of these assets.

In the various embodiments of the present invention as described herein,the electrical assets are described as industrial electric motors thatare used in an industrial process such as a power generation operation.In one embodiment, the electric motors are three-phase motors such asinduction motors and synchronous motors. Although the variousembodiments of the present invention are described with respect topresenting unbalance information generated from electric motors used ina power generation operation in a manner that facilitates monitoring andmanagement of the motors, the embodiments of the present invention arenot limited to use solely with motors that operate in a power generationoperation. Those skilled in the art will recognize that the variousembodiments of the present invention can be used to manage otherelectric assets that operate in any process that generates unbalanceinformation or other analogous operational data that can be used tomanage and monitor these assets.

Referring to the drawings, FIG. 1 is a schematic block diagram of asystem 100 for managing motors operating in a process. As shown in FIG.1, system 100 includes motors (i.e., Motor 1, Motor 2 . . . . Motor n)110 that in one embodiment are three-phase motors that operate in apower generation plant. A motor protection system 120 protects motors110 from failing by protecting against items that may include unbalancedloads, excessively high overcurrent faults, undervoltage conditions,overvoltage conditions, mechanical jams and load losses. Performingthese functions as well as other motor protection functionalities arewidely well known in the art of motor protection devices and therefore adetailed description of these functions is not provided.

For the sake of simplicity in illustrating embodiments of the presentinvention, those skilled in the art will recognize that not all featuresand functionalities associated with using motor protection system 120are illustrated in FIG. 1. For example, those skilled in the art willappreciate that motor protection system 120 will have inputs and outputscoupled to various sensors and transducers that measure variousparameters of the power generation process. In addition, those skilledin the art will recognize that motor protection system 120 would haveseveral inputs for each of the motors 110. An illustrative, butnon-exhaustive, listing of inputs would include phase voltage inputs,current inputs and differential inputs. Other inputs could includeconnections to receive data from the windings and bearings of the motors110, as well as some of the devices (e.g., pumps, compressors) driven bythese motors.

Motor protection system 120 may be any commercially available motorprotection device such as an electric meter or relay. One example of acommercially available motor protection device that may be used insystem 100 is a 469 Motor Management Relay sold by GE Multilin. Thoseskilled in the art will recognize that there are other commerciallyavailable motor protection devices that perform functions and generateinformation similar to the 469 Motor Management Relay.

Referring back to FIG. 1, computers 130 connect to the motor protectionsystem 120 via a communications network 140. Computers 130 can be usedto perform one of a variety of operations. For example, one computer 130can be a host computer that is at a remote location that is used toperform remote monitoring and diagnostics of the motors 110, as well asgeneral management of these assets. Another computer 130 may be locatedlocally about the motor protection system 120, so that a plant operatorcan have closer interaction with the system at the process level.Regardless of where computers 130 are located, they can be used toimplement the various embodiments of the present invention. Computers130 have an electrical asset management application as described hereinwith respect to the various embodiments of the present invention, thatconfigures the computers to receive unbalance information generated fromthe motors 110 that is obtained by motor protection system 120 andtransform this information in a presentable manner that can be used tomonitor and manage (e.g., troubleshoot problems) the motors as well asother assets used in the power generation operation.

For a typical ungrounded three-wire, three-phase motor such as aninduction motor, an installer and operator have three wires to connectand operate. Carried within each wire is a phase current measureablewith an ammeter and between any two wires is a line-to-line voltagemeasureable by a voltmeter. For a perfect system, the measuredmagnitudes of the voltages should equal each other and the measuredmagnitudes of the current should equal each other. As used herein,“balance” refers to identical line-to-line voltage magnitudes and phasecurrents.

Unbalanced voltage is a measureable deviation from perfection, definedby the National Electric Manufacturer's Association (NEMA) and theInstitute of Electrical and Electronics Engineers (IEEE), to be theabsolute value of the largest deviation from the mean, divided by themean, in percent. For example, NEMA Motors and Generators 1 standard(MG1) gives the example of readings for a 460 volt motor of 460, 450 and467 volts. The arithmetic average is ⅓(460+450+467)=459. The largestdeviation from 459 is from 450, with a value of 9. The unbalance voltagepercentage is 100×(9/459)=1.96%. Unbalanced voltage causes a number ofdetrimental effects to an induction motor, including excessive statorcurrents and rotor currents. Those skilled in the art of motorapplications will recognize that voltage unbalance causes negativesequence effects on the rotor correlated to the voltage unbalance atnearly twice line frequency. The nearly 120 Hertz (Hz) currents on a 60Hz device cause the conducting components of the rotor to generate heat,overloading the cooling capacity of the motor. In addition, a pronounced120 Hz noise will emanate from the stator core. NEMA standard MG1-2000states that an unbalance of 1.96% as calculated above causes the motorto run at best 95% of its rating. Further, this standard indicates thata voltage unbalance of 3% reduces the rating to 88% and a voltageunbalance of 4% reduces the rating to 82%, which is well below where aneconomically sized motor carrying a load at 90% or more would bethermally safe to run.

Unbalanced current is computed in a similar manner using the phasemagnitudes. However, modern practice recognizes that for a given voltageunbalance, the current unbalance may be four to six times that valuebased upon how a symmetrically constructed machine reacts to theimperfect voltage supply. It also recognizes that a lightly loaded motorcan withstand imperfection better than a heavily loaded one based uponits cooling system limits. Therefore, unbalanced current is definedherein is:

Unbalanced current=100%×(Maximum deviation Phase Current/AverageCurrent) If the average current is>=Nameplate Current

=Unbalanced current per above x % Nameplate Amps If the average currentis<Nameplate Current

Typically, the unbalance information generated by the motor protectionsystem 120 is a numerical value of the current balance or voltageunbalance. This information in this form is not very meaningful to anoperator for several reasons and thus is not helpful in the monitoringor troubleshooting of motors 110. One reason why the currently availableunbalance information is not very meaningful is that there are typicallyno communications systems available to report the data automatically toa central location. The great number of operators today must interrogatea microprocessor-based relay locally at the motor control center toestablish the information. For example, in a conventional system, thereis no motor control system. Typically, a relay is slaved to a motorcontrol center and there is no communications. Usually, there is just aset of wires to command “Run” and echoing signals to state “Running” or“Tripped”. As a result, the operators must interrogate detailed statusinformation or outputs at the motor protection device to establishoperating information. Another reason why the currently availableunbalance information is not very meaningful is because, depending uponthe age of the technology, the local calculation of unbalance forvoltage or current may not be available and the basic values tocalculate them may not be outputs of the motor protection device. Manydevices only tell the operator why they have tripped a machine withoutbenefit of steady state or pre-trip values.

As described herein, the electric asset management applicationconfigured to run on computers 130, is configured to transform theunbalance information in a representation that clearly facilitates theimpact this data can have on motors 110 as well as the process in whichthe motors operate. In particular, the electric asset managementapplication according to various embodiments of the present inventiongenerates a visual representation of motors 110 operating in theprocess, partitions the motors in this representation into one or moregroupings that are each based on a common operational characteristic,associates the respective unbalance information with each of the motorsin the one or more groupings and determines at least one statisticalmeasure for each of the one or more groupings that is based on theunbalance information associated with each of the motors in the one ormore groupings. The at least one statistical measure provides anindication of the presence of abnormal operation associated with each ofthe one or more groupings and generates a visual representation thisinformation in a display to an operator.

FIG. 2 shows a flow chart 200 illustrating the operation of using theelectric asset management application to generate screen views that maybe used to facilitate management of motors 110 shown in FIG. 1 accordingto one embodiment of the present invention. Flow chart 200 of FIG. 2begins by generating a visual representation of the motors 110 operatingin the industrial process at 210. The visual representation is generallya graphical representation of all of the assets operating in theprocess. The visual representation can be generated earlier using anysoftware package that has the capability to generate graphics. In oneembodiment, before the visual representation is generated, a plantengineer could evaluate his or her I-line diagrams to capture motor andnon-motor electrical loads (e.g., electric heaters, etc.) that arecritical to the process. The output of his or her thought and drawingprocess would be a I-line diagram such as one shown in FIG. 3.

FIG. 3 shows an example of a screen view 300 that may be generated thatprovides a visual representation of the motors 110 (FIG. 1) operating inthe process. In particular, the screen view 300 of FIG. 3 shows theauxiliary machinery of a power generation plant characterized by severalsub-processes having motors coupled to a common electrical bus. As shownin the representation of FIG. 3, a 34.5 kilovolt (kV) utility powerconnects to a three-phase transformer (XFMR-1) that splits this voltageamong a primary transformer (i.e., the top circle of XFMR-1) and twosecondary transformers (i.e., the right-hand circle and left-hand circleof XFMR-1). In particular, secondary transformer on the right-hand sideof XFMR-1 generates a 13.8 kV voltage that is provided along a voltagebus, whereas the secondary transformer on the left-hand side of XFMR-1generates a 4160 V voltage that is provided along a voltage bus. Asshown in FIG. 3, the 13.8 kV voltage bus feeds three very largemotor/compressor sets that are used for different processes. In FIG. 3,one motor/compressor set that is in this region is designated by anMC-001. The prefixes 1, 2 and 3 that precede MC-001 are used todesignate that each motor/compressor set is used in one of threesub-processes or processes.

The 13.8 kV voltage bus also feeds a self-contained process skid (e.g.,a small lube oil supply skid) by a long cable via a step-downtransformer (XFMR-4) with fixed taps. As shown in FIG. 3, theself-contained process skid comprises several motor/pump sets. In FIG.3, the motor/pump sets that are in this region are designated by 4-MP.The suffixes 001A, 001B and 002 designate the motor/pump set used insub-process or process 4. In addition, the self-contained process skidcomprises a small heater (e.g., for oil viscosity control on cold days)that is designated by 4-HTR-001. Sub-process or process 2 comprisesmotor/pump sets 2-MP-002, 2-MP-003 and 2-MP-004. Note that motor/pump2-MP-004 receives 480V via a step-down transformer XFMR-2 that reducesthe 4160V to the 480V. In addition to the motor/pump sets, process 2includes a heater represented by 2-HTR-001.

As shown in FIG. 3, sub-process or process 3 is coupled to the 4160 Vbus via a long 3-phase cable run. Sub-process or process 3 is shown ascomprising a multiple of motor/pump sets 3-MP-002, 3-MP-003, 3-MP-004and 3-MP-005. Note that motor/pump 3-MP-005 receives 480V via astep-down transformer XFMR-3 that reduces the 4160V to the 480V. Inaddition to the motor/pump sets, process 3 includes two heatersrepresented by 3-HTR-001 and 3-HTR-002. Note that heaters 2-HTR-0013-HTR-001 and 3-HTR-002 may be continuous loads or may have onlystart-up and shutdown duty depending upon availability of steam to dothe same job.

Referring back to flow chart 200 of FIG. 2, the next step is topartition (e.g., arrange, organize, etc.) the motors 110 in the visualrepresentation into one or more groupings at 220. That is, the plantengineer being an individual skilled in the art and understandingunbalance, could now partition his or her work from the generated I-linediagram (e.g., FIG. 3) by what his or her experience tells indicates iscritical. In one embodiment, each of the groupings is based on a commonoperational characteristic associated with the motors 110. In a firstembodiment, the common operational characteristic associated with themotors 110 that is used to partition these assets into one or moregroupings is the voltage level of the electric bus that each motorconnects thereto. In another embodiment, the common operationalcharacteristic that is used to partition the motors into one or moregroupings is the sub-process or process that each of the motors operatewithin the process. An example of a sub-process or process that could beused to partition the assets includes critical circuitbreakers/transformers. Although the description that follows pertains tousing the electric bus and sub-process or process to partition themotors 110 into one or more groupings, those skilled in the art willrecognize that other operational characteristics may be used topartition the motors. For example, other operational characteristicsthat may be used to partition the motors may include motors groupedunder a particular set of line fuses or any other electrical elementwithin the plant that may fail in an asymmetrical way (i.e., one or twoof the three phases may act, but not all three).

In one embodiment, the partitioning of the motors 110 in the visualrepresentation into one or more groupings is generated by laying outgraphical lines around the desired portions of the visual representationthat are representative of the operational characteristics that form thebasis for the groupings. These groupings or partitions may beaccomplished one screen per partition using a dashed box, a colorcoding, or any other visual means provided by a typical graphicalsoftware application to designate subset commonality.

FIG. 4 shows an example of a screen view 400 that may be generated uponpartitioning the motors into one or more groupings based on a commonoperational characteristic. In particular, FIG. 4 shows the partitioningof the motors into groups that are based on the common voltage bus thateach motor connects thereto. As shown in FIG. 4, there are three groups;Group 1 is the 13.8 kV bus, Group 2 is the 4160 V bus and Group 3 is the480 V bus used in the self-contained process skid. In particular, Group1 includes motor/compressor sets 1-MC-001, 2-MC-001 and 3-MC-001; Group2 includes motor/pump sets 2-MP-002, 2-MP-003, 2-MP-004, 3-MP-002,3-MP-003, 3-MP-004 and 3-MP-005; and Group 3 includes motor/pump sets4-MP-001A, 4-MP-001B and 4-MP-002.

FIG. 5 shows another example of a screen view 500 that may be generatedupon partitioning the motors into one or more groupings based on acommon operational characteristic. In particular, FIG. 5 shows thepartitioning of the motors into groups that are based on the commonsub-process or process that each motor is within. As shown in FIG. 5,there are four groups; Sub-Process 1 includes motor/compressor sets1-MC-001, 2-MC-001 and 3-MC-001; Sub-Process 2 includes motor/pump sets2-MP-002 and 2-MP-003 coupled to the 4160V bus and 2-MP-004 coupled tothe 480 V bus which is coupled to the 4160V bus via the step-downtransformer (XFMR-2); Sub-Process 3 includes motor/pump sets 3-MP-002,3-MP-003 and 3-MP-004 coupled to the 4160V bus and 3-MP-005 coupled tothe 480 V bus which is coupled to the 4160V bus via the step-downtransformer (XFMR-3); and Sub-Process 4 includes motor/pump sets4-MP-001A, 4-MP-001B and 3-MP-002. As shown in FIG. 5, the processes aresegregated only at the 4160 V bus and lower due to the large “singleton”13.8 kV motors that are best addressed at the bus level. Since processesgenerally tend to occur in spatial groups or skids, these can be groupedto monitor for trends. In the example shown in FIG. 5, if the main feedfrom transformer XFMR-1 to the 4160V bus were in distress, Sub-Process 2would best catch it. However, if the long feeder to Sub-Process 3 fromSub-Process 2 is misconnected or damaged over time, it warrantsSub-Process 3 having its own summary statistics for observation. Bysimilar reasoning, Sub-Process 4 needs to be monitored at the end of itscable.

Note that in both FIGS. 4 and 5, the heaters (i.e., 2-HTR-001,3-HTR-001, 3 HTR-002 and 4-HTR-001) are not shown since they typicallyhave no real-time instrumentation. Also, note that the 480V transformers(XFMR-2 and XFMR-3) and their loads are grouped with the 4160 V bus.This is done because the transformers are assumed to have fixed taps andare balanced. If they were tap-changing under load and had the abilityto hang a phase's tap, they would be designated as separate groups.

Referring back to flow chart 200 in FIG. 2, the next step is to obtainthe unbalance information generated from the motors 110 (FIG. 1) at 230while in operation from the motor protection system 120 (FIG. 1). In oneembodiment, the obtaining of the unbalance information from the motorprotection system is performed by any one of currently availableelectronic communications systems (not shown), e.g., Modbus, Prophibus,Foundation Field Bus, Ethernet, etc. Depending upon the sophisticationof the system, a relay may only transmit to or may send and receive datafrom a communications circuit in a computer system, the latter beingtypically used in more modern methods.

After obtaining the unbalance information, the electric asset managementapplication then associates the respective unbalance information witheach of motors 110 (FIG. 1) in the one or more partitioned groups at240. In particular, the electric asset management application maps theunbalance information generated from each motor (FIG. 1) that wasreceived by the motor protection system 120 (FIG. 1) to the partitionedgrouping that contains that respective motor. In one embodiment, theassociating of the unbalance information from the motor protectionsystem to the partitioned grouping containing that motor is performed byattributes assigning of the data from the communications system tovariable names with the computer 130 (FIG. 1).

With the unbalance information associated with each of the motors intheir respective partitioned groupings, the electric asset managementapplication can determine at least one statistical measure for each ofthe one or more groupings at 250 in order to determine if there isabnormal operation in a group. The at least one statistical measure isbased on the unbalance information associated with each of motors 110(FIG. 1) in the one or more partitioned groups. In one embodiment, theat least one statistical measure may comprise a measure of centraltendency such as the mean, mode or median, and a measure of spread invalues, such as a range or standard deviation, or coefficient ofvariation (e.g., standard deviation and mean that is dimensionless).Those skilled in the art will recognize that any one of a number ofstatistical measures can be determined and that the various embodimentsof the present invention should not be limited to any particularmeasure. Other examples of possible statistical measures that can becomputed include median and mode for the measure of central tendency andrange for variability.

In the various embodiments of the present invention, the at least onestatistical measure could be determined by using the mathematicalprocessor within the computer 130 (FIG. 1). As an example, a simplearithmetic mean of Group 1 in FIG. 4 could be determined in thefollowing manner where N=3:

Average Voltage Unbalance of Group 1=1/N×(Voltage Unbalance(1-MC-001)+Voltage Unbalance (2-MC-001)+Voltage Unbalance (3-MC-001))

A statistical measure that captures variability in this example could bedetermined as:

Standard Deviation of Group 1=square root of (((Voltage Unbalance(1-MC-001)−Average)̂2+(Voltage Unbalance (2-MC-001)−Average)̂2+(VoltageUnbalance (3-MC-001))−Average)̂2))/(N−1)),

where “Average”=Average Voltage Unbalance of Group 1.

Referring back to FIG. 2, after generating the at least one statisticalmeasure, the electric asset management application generates a screenview at 260 that provides the visual representation of the motors aspartitioned within the one or more groupings, the unbalance informationassociated with each of the motors in the one or more groupings and theat least one statistical measure associated with each of the groupings.In one embodiment, this type of screen view is generated by the use ofscreen graphics provided by a typical graphical software application. Inone embodiment, the lines forming the grouping would be static, however,the statistics associated with the groupings would be constantly updatedat the standard screen refresh interval. Depending upon howextraordinary events are handled, the screen graphics could also changecolors of borders or regions (e.g., change from yellow or red) toindicate a severe condition.

FIGS. 6 and 7 show examples of screen views 600 and 700, respectivelythat may be generated by the electric asset management application upondetermining the at least one statistical measure. In particular, FIGS. 6and 7 show the voltage and current unbalance associated with each of thepartitioned groups. More specifically, FIG. 6 shows that Group 1 has anaverage percentage of voltage unbalance of 0.4, a standard deviation ofpercentage voltage unbalance of 0.1, an average of percentage of currentunbalance of 2.43 and a standard deviation of percentage of currentunbalance of 0.40; Group 2 has an average percentage of voltageunbalance of 1.49, a standard deviation of percentage voltage unbalanceof 0.24, an average of percentage of current unbalance of 8.8 and astandard deviation of percentage of current unbalance of 1.70; Group 3has an average percentage of voltage unbalance of 0.77, a standarddeviation of percentage voltage unbalance of 0.06, an average ofpercentage of current unbalance of 4.4 and a standard deviation ofpercentage of current unbalance of 0.56; and for the total overallprocess there is an average percentage of voltage unbalance of 1.07, astandard deviation of percentage voltage unbalance of 0.52, an averageof percentage of current unbalance of 6.32 and a standard deviation ofpercentage of current unbalance of 3.13. FIG. 7 shows that Sub-Process 1has an average percentage of voltage unbalance of 0.4, a standarddeviation of percentage voltage unbalance of 0.1, an average ofpercentage of current unbalance of 2.43 and a standard deviation ofpercentage of current unbalance of 0.40; Sub-Process 2 has an averagepercentage of voltage unbalance of 1.27, a standard deviation ofpercentage voltage unbalance of 0.15, an average of percentage ofcurrent unbalance of 8.03 and a standard deviation of percentage ofcurrent unbalance of 2.61; Sub-Process 3 has an average percentage ofvoltage unbalance of 1.65, a standard deviation of percentage voltageunbalance of 0.13, an average of percentage of current unbalance of 9.38and a standard deviation of percentage of current unbalance of 0.45;Sub-Process 4 has an average percentage of voltage unbalance of 0.77, astandard deviation of percentage voltage unbalance of 0.06, an averageof percentage of current unbalance of 4.4 and a standard deviation ofpercentage of current unbalance of 0.56; and for the total overallprocess there is an average percentage of voltage unbalance of 1.07, astandard deviation of percentage voltage unbalance of 0.52, an averageof percentage of current unbalance of 6.32 and a standard deviation ofpercentage of current unbalance of 3.13.

FIGS. 6 and 7 further show individual voltage unbalance information andcurrent unbalance information associated with motors in a grouping. Inparticular, FIG. 6 shows that in Group 1, motor/compressor set 1-MC-001has a percentage of voltage unbalance of 0.3 and a percentage of currentunbalance of 2.0; motor/compressor set 2-MC-001 has a percentage ofvoltage unbalance of 0.5 and a percentage of current unbalance of 2.8;motor/compressor set 3-MC-001 has a percentage of voltage unbalance of0.4 and a percentage of current unbalance of 2.5; motor/pump set2-MP-004 has a percentage of voltage unbalance of 0.7 and a percentageof current unbalance of 3.8; and motor/pump set 3-MP-005 has apercentage of voltage unbalance of 0.8 and a percentage of currentunbalance of 4.5. FIG. 7 shows that in Group 1, motor/compressor set1-MC-001 has a percentage of voltage unbalance of 0.3 and a percentageof current unbalance of 2.0; motor/compressor set 2-MC-001 has apercentage of voltage unbalance of 0.5 and a percentage of currentunbalance of 2.8; and motor/compressor set 3-MC-001 has a percentage ofvoltage unbalance of 0.4 and a percentage of current unbalance of 2.5.Although FIGS. 6 and 7 do not show the individual voltage unbalanceinformation and current unbalance information associated with eachmotor, those skilled in the art will recognize that this informationcould be listed beside each individual motor in a grouping.

Those skilled in the art will recognize that these screen views are onlyexamples of how unbalance information and statistical measures may bepresented to an operator using the electric asset management applicationrunning on computers 130 (FIG. 1) and that there other manners ofpresenting this information as well other statistical measures that canbe provided to the operator.

Referring back to FIG. 2, the statistical measures are used at 270 todetermine if it is necessary to generate an alert notification thatrequests that the operator investigate further into the operatingcondition of the motors. In one embodiment, the generated statisticalmeasures can be compared to predetermined threshold limits to determineif it is necessary to generate an alert notification. If any one of themeasures exceeds the predetermined threshold limits then relays coupledto the motors can be automatically tripped so that the operator caninvestigate further into why the measures exceeded the thresholds (e.g.,this may be suitable in scenarios where there is severe unbalance). Inanother embodiment, a notification can be sent to the operatorindicating that a statistical measure has exceeded a predeterminedthreshold limit. In this embodiment, those skilled in the art willrecognize that the notification can be provided through one of manypossible notification mediums. For example, the notification can beaudible (e.g., an alarm), visual (e.g., notifications indicating thetype of distress (e.g., red lights provided on a status displayindicating a serious condition and yellow lights indicating a potentialissue)), textual (e.g., an email in color coded text) or combinations ofboth. After receiving any one of these notifications, the plant operatorcan take appropriate action to initiate an investigation as to why thepredetermined threshold limits were exceeded.

With information presented in this manner, an operator is bettersituated to monitor and manage the motors as well as the entire processin which the motors are operating within. For example, an operatorreferring to FIGS. 4 and 6 (grouping by voltage bus), could use thesescreen views to identify a problem attached to the voltage bus. Forinstance, if all running motors attached to a voltage bus are indicatingthe same approximate voltage unbalance, then it is likely that theproblem is not a motor issue, but due to another large load on that bus.Thus, post-processing the unbalance information with a mean and standarddeviation by voltage bus will help the operator or other system softwareto quickly identify a system problem unrelated to the individual motors.Similarly, an operator referring to FIGS. 5 and 7 (grouping bysub-process), could use these screen views to identify a failure withina sub-process or pre-packaged unit within the power generation plant. Iffor example the mean moves slightly and the variability is large, then asingle motor is likely in trouble and needs to be visited by a planttechnician. If for example, the average of all of the motors in aprocess were high and the standard deviation was low, then this would bean indication to the operator that there are no problems with motors 110(FIG. 1) and that the problem is likely due to some other component inthe industrial process. For example, the heaters or other large loadsthat are a significant fraction of the motor load may have becomeunbalanced due to degradation or a misconnection. The scenarios thatembodiments of the present invention can be used to explain or identifyfailures with motors 110 (FIG. 1) or the entire power generation processwith the unbalance information are plentiful and cannot all be describedherein, although it is intended that those skilled in the art could usethe teachings herein to recognize and identify these failures.

The foregoing flow chart of FIG. 2 shows some of the processingfunctions associated with generating screens that present unbalanceinformation in a manner that facilitates monitoring and management ofmotors in an industrial process. In this regard, each block represents aprocess act associated with performing these functions. It should alsobe noted that in some alternative implementations, the acts noted in theblocks may occur out of the order noted in the figure or, for example,may in fact be executed substantially concurrently or in the reverseorder, depending upon the act involved. Also, one of ordinary skill inthe art will recognize that additional blocks that describe theprocessing functions may be added.

In various embodiments of the present invention, computers 130 can takethe form of an entirely hardware embodiment, an entirely softwareembodiment or an embodiment containing both hardware and softwareelements. In a preferred embodiment, the processing functions performedby electric asset management application running on computer 130 areimplemented in software, which includes but is not limited to firmware,resident software, microcode, etc.

Furthermore, the processing functions performed by the electric assetmanagement application running on the computer 130 can take the form ofa computer program product accessible from a computer-usable orcomputer-readable medium providing program code for use by or inconnection with a computer or any instruction execution system. For thepurposes of this description, a computer-usable or computer readablemedium can be any computer readable storage medium that can contain orstore the program for use by or in connection with the computer,instruction execution system, apparatus, or device or a computerreadable transmission medium that can communicate, propagate ortransport the program for use by or in connection with the computer,instruction execution system, apparatus, or device.

The computer readable medium can be an electronic, magnetic, optical,electromagnetic, infrared, or semiconductor system (or apparatus ordevice) or a propagation medium. Examples of a computer-readable mediuminclude a semiconductor or solid state memory, magnetic tape, aremovable computer diskette, a random access memory (RAM), a read-onlymemory (ROM), a rigid magnetic disk and an optical disk. Currentexamples of optical disks include a compact disk-read only memory(CD-ROM), a compact disk-read/write (CD-R/W) and a digital video disc(DVD).

While the disclosure has been particularly shown and described inconjunction with a preferred embodiment thereof, it will be appreciatedthat variations and modifications will occur to those skilled in theart. Therefore, it is to be understood that the appended claims areintended to cover all such modifications and changes as fall within thetrue spirit of the disclosure.

1. A computer system for presenting unbalance information from aplurality of electrical assets operating in a process, the computersystem comprising: at least one processing unit; memory operablyassociated with the at least one processing unit; and an electricalasset management application storable in memory and executable by the atleast one processing unit that presents the unbalance informationgenerated from the plurality of electrical assets for managementthereof, the electrical asset management application configured to:generate a visual representation of the plurality of electrical assetsoperating in the process; partition the plurality of electrical assetsin the visual representation into one or more groupings that are eachbased on a common operational characteristic associated with theplurality of electrical assets; obtain the unbalance information andassociate the unbalance information with each of the plurality ofelectrical assets in the one or more groupings; determine at least onestatistical measure for each of the one or more groupings that is basedon the unbalance information associated with each of the plurality ofelectrical assets in the one or more groupings, wherein the at least onestatistical measure provides an indication of the presence of abnormaloperation associated with each of the one or more groupings; and displaythe visual representation of the plurality of electrical assets aspartitioned within the one or more groupings, the display furthercomprising the unbalance information associated with each of theplurality of electrical assets in the one or more groupings and the atleast one statistical measure associated with each of the one or moregroupings.
 2. The computer system according to claim 1, wherein thecommon operational characteristic associated with the plurality ofelectrical assets that is used to partition the assets into one or moregroupings comprises voltage of an electrical bus that each of theplurality of electrical assets connect therewith or a sub-process thateach of the plurality of electrical assets operate within.
 3. Thecomputer system according to claim 1, wherein the at least onestatistical measure comprises a measure of central tendency of theunbalance information of the electrical assets within each of the one ormore groupings and a measure of spread of the unbalance information ofthe electrical assets within each of the one or more groupings.
 4. Thecomputer system according to claim 1, wherein the unbalance informationcomprises voltage unbalance.
 5. The computer system according to claim4, wherein the electrical asset management application is furtherconfigured to determine the current unbalance from the voltageunbalance.
 6. The computer system according to claim 5, wherein theelectrical asset management application is further configured to displaythe current unbalance and the voltage unbalance that is associated witheach of the plurality of electrical assets in each of the one or moregroupings.
 7. The computer system according to claim 1, wherein theelectrical asset management application is further configured todetermine if the at least one statistical measure warrants generating anotification indicating the presence of operational issues associatedwith any one of the plurality of electrical assets.
 8. A method,performed on a computer system, for monitoring a plurality of electricalassets operating in a process, the method comprising: using the computersystem to perform the following: displaying a screen view that providesa visual representation of the plurality of electrical assets operatingin the process; displaying a screen view that facilitates partitioningthe plurality of electrical assets in the visual representation into oneor more groupings that are each based on a common operationalcharacteristic associated with the plurality of electrical assets;obtaining unbalance information generated from the plurality ofelectrical assets as each operates in the process; associating theobtained unbalance information with each of the plurality of electricalassets in the one or more groupings; determining at least onestatistical measure for each of the one or more groupings that is basedon the unbalance information associated with each of the plurality ofelectrical assets in the one or more groupings, wherein the at least onestatistical measure provides an indication of the presence of abnormaloperation associated with each of the one or more groupings; anddisplaying a screen view that provides the visual representation of theplurality of electrical assets as partitioned within the one or moregroupings, the unbalance information associated with each of theplurality of electrical assets in the one or more groupings and the atleast one statistical measure associated with each of the one or moregroupings.
 9. A method according to claim 8, wherein the commonoperational characteristic associated with the plurality of electricalassets that is used to partition the assets into one or more groupingscomprises voltage of an electrical bus that each of the plurality ofelectrical assets connect therewith or a sub-process that each of theplurality of electrical assets operate within.
 10. The method accordingto claim 8, wherein the at least one statistical measure comprises ameasure of central tendency of the unbalance information of theelectrical assets within each of the one or more groupings and a measureof spread of the unbalance information of the electrical assets withineach of the one or more groupings.
 11. The method according to claim 8,wherein the unbalance information comprises voltage unbalance.
 12. Themethod according to claim 11, further comprising determining the currentunbalance from the voltage unbalance.
 13. The method according to claim12, further comprising displaying a screen view that provides thecurrent unbalance and the voltage unbalance that is associated with eachof the plurality of electrical assets in each of the one or moregroupings.
 14. The method according to claim 8, further comprisingdetermining if the at least one statistical measure warrants generatinga notification indicating the presence of operational issues associatedwith any one of the plurality of electrical assets.
 15. Acomputer-readable storage medium storing computer instructions, whichwhen executed, enables a computer system to present unbalanceinformation generated from a plurality of electrical assets operating ina process, the computer instructions comprising: generating a visualrepresentation of the plurality of electrical assets operating in theprocess; partitioning the plurality of electrical assets in the visualrepresentation into one or more groupings that are each based on acommon operational characteristic associated with the plurality ofelectrical assets; obtaining the unbalance information from theplurality of electrical assets as each operates in the process;associating the obtained unbalance information with each of theplurality of electrical assets in the one or more groupings; determiningat least one statistical measure for each of the one or more groupingsthat is based on the unbalance information associated with each of theplurality of electrical assets in the one or more groupings, wherein theat least one statistical measure provides an indication of the presenceof abnormal operation associated with each of the one or more groupings;and generating a screen view that provides the visual representation ofthe plurality of electrical assets as partitioned within the one or moregroupings, the unbalance information associated with each of theplurality of electrical assets in the one or more groupings and the atleast one statistical measure associated with each of the one or moregroupings.
 16. The computer-readable medium according to claim 15,wherein the common operational characteristic associated with theplurality of electrical assets that is used to partition the assets intoone or more groupings comprises voltage of an electrical bus that eachof the plurality of electrical assets connect therewith or a sub-processthat each of the plurality of electrical assets operate therein.
 17. Thecomputer-readable medium according to claim 15, wherein the at least onestatistical measure comprises a measure of central tendency of theunbalance information of the electrical assets within each of the one ormore groupings and a measure of spread of the unbalance information ofthe electrical assets within each of the one or more groupings
 18. Thecomputer-readable medium according to claim 15, wherein the unbalanceinformation comprises voltage unbalance.
 19. The computer-readablemedium according to claim 18, further comprising instructions fordetermining the current unbalance from the voltage unbalance.
 20. Thecomputer-readable medium according to claim 19, further comprisinginstructions for displaying a screen view that provides the currentunbalance and the voltage unbalance that is associated with each of theplurality of electrical assets in each of the one or more groupings.